Exhaust fans are provided beneath respective motors of an unmanned aerial vehicle (UAV), or alternatively, centrifugal fans are provided within respective motors. While the UAV is operating, the air internal to the UAV body is pumped out, and a negative pressure is generated within the UAV body. This negative pressure within the UAV body adversely affects barometric measurement sensors, such as those within an inertial measurement unit, as the pressure within the body of the UAV is not necessarily representative of pressure external to the UAV.